Carburetor



ug., i2, 1930.

CARBURETOR Filed Jan. ze, 1923 Giacomo mamml.

fto rney.

lmatented flug. l2, i939 Giacomo ummm, on mLAnrrALY GARBURETO'R Application filed January 26, 1923, Serial No.l615,050, and

The object of the present invention is to vary the amount ot the tuel fed through the nozzle ot a carburetor for internal combustion engines, so that less fuel is supplied progressively and proportionately as trie suction at said nozzle increases, this etlect being obtained automatically and without employment of any movable controlling device.

In the attached drawing, Fig. l shows diagrammatically a. longitudinal section taken on theline l-l, Fig. 2, and 2 a cross section, ot this device tor actuating said control in a common carburetor, taken on the line 2-2, Fig. l. rllhe arrangement may vary according to the shape ot the carburetor.

l represents thevtloat chamber, Q. the passage connecting it with the mixing chamber through the restricted orilice 8 which leads into a chamber l0 containing the two extremi-l ties of an annular passage 5, 5, 5', 5", 5"',

one otl these extremities communicating cirect-ly with the part 5 ot said annular passage, which is ot airly ample section and which communicates through the nozzle 4 with the mixing chamber 9 in the Venturi throat 7 ot the latter, and in certain cases through the narrow passage 6 (in the portion 5" and at a certain distance trom the nozzle 4) with the atmosphere; the portion 3o 5"', which forms the other extremity ot the annular passage, than the rest ot the passage. 8 is the throttle valve which closes the mixing chamber.

rThe operation of the device is as follows:

From the tloatchamber l the Jfuel passes,

through the passage 2 to the restricted oriiice 3, from the orifice 3 the fuel rises in the chamber 10 passage 5'l and the nozzle 4, up

to the level existing in l.

When the throttle valve .8 is slightly opened and the engine started up, a low depression is exerted through the Venturi throat 7 and a small depression through the nozzle 4, so that said nozzle 4 will be continuously ted by the orifice 3, not owing to the suction on the latterA at this moment, but because the fuel has a. tendency to pass from the lioat chamber 1, and-according to the welllrnown law of the constant level or liquids-rise to the same level in the passages communicating is ot lesser cross section.

in any February 25, 1922.

with it. It the opening of the throttle v 8 be increased, the depression through alve the Venturi throat 7, and consequently through the nozzle 4, Will be greater; but the portions 5', 5 and l() will be emptied and through the portion 5 there will be formed a continuous passage from the orifice 3 to the nozzle 4 ,and

through 5"', 5", 5',

5, a depression Willbe exerted in chamber l0 dueto the passage ot air from the passage 5 to the nozzle so that thev flow of uel fromB to 5 uted or counteracted will be distribby eddies Jforming in the lower kpart ot chamber l() where the depression acts upon the lsurface, of the fuel.

The portion 5 is at this time eithercompletely' or almost completely lille-d with therebyhindering or stopping entirely How of air therethrough.

tuel the On opening the throttlev valve 8 still more,

or completely, there will be still greater pression on the nozzle 4, and at the same time there will also be increased the passages 5, 5', 5"

depression in and 5"', and as this de pression exerts an opposite action on the main suction through 5 there will be at this ment two opposite forces, that is, the or moilice 3 will be no longer subjected to the total depression of thenozzle 4,

through portion 5,

but to a much lesser degree in view of the depression exerted through 5" sultinv eddies Within chamber l0' there and to the retore the fuel can reach the nozzle 4 through 5 only in relatively small quantities.

ln the portion 5" there is a restricted air passage 6, which in certain cases may not be necessary, the general eltect ot same bein delay'or partially gto counteract the effect ot the suction through 5"', 5", 5', 5 as thedepression exerted from the nozzle 4 only influences the portion 5"' when it has increased to such a value as to overcome the air supplying capacity of the restricted fore theportion 5" passage 6, andthereoperates in the above described manner only when the depression from 4 exceeds a predetermined value. Said passage 6 is also provided with the object of moderating the action ot' the controlling device, so that the latter should be too strong and not of the carburetor under full load.

l not hinder the working What I claim is l. A device for the automatic control of the fuel flow from the fuel nozzle of a carburetor, comprising a fuel chamber between the usual float chamber and the fuel nozzle, a restricted orifice for the supply of fuel to said chamber, the crossesectional area of this orifice being less than that of the nozzle, a fuel passage for the supplg,T of fuel from the said chamber to the fuel nozzle, and an air passage having a portion of lesser crosssectional area than the first passage and leading from the top of said chamber to the nozzle to create eddies in suoli chamber and thus oppose the flow of fuel to the nozzle in proportion as the depression at the nozzle increases.

2. A device for the automatic control of the fuel flow from the fuel nozzle of a carburetor, comprising a fuel chamber between the usual float chamber and the fuel nozzle, means for restricting the flow of fuel to the said chamber, a fuel supply passage from the said chamber to the nozzle, and an air passage of greater length but having a portion thereof of lesser cross's'ectional area than the first passage and also providing communication between the-said chamber and nozzle to create eddies in said chamber and thus oppose the flow of fuel to the nozzle in proportion as the depression at the nozzle increases.

3. A device for the automatic control of the fuel flow from the fuel nozzle of a carburetor, comprising a fuel chamber between the usual float chamber and the fuel nozzle, means for restricting the flow of fuel from the float chamber, a fuel supply passage leading from the said fuel chamber to the nozzle, an air passage of greater length than the .first passage but having a part of lesser cross-sectional area and also providing communication between such fuel chamber and the nozzle for the purpose of creating eddies in the said fuel chamber and thus opposing the flow of fuel to the nozzle in proportion as the depression at the nozzle increases, and a restricted passage providing communicai tion between the said air passage and the atmosphere.

4. A device for the automatic control of the fuel flow from the fuel nozzle of a carburetor, comprisinga fuel chamber between the usual float chamber and the fuel nozzle, a fuel supply passage from the lower part of said chamber to the nozzle, an air passage having a portion of lesser cross-sectional area than the first passage Vandproviding Ycoirlniunication between the upper part of said chamber and the fuel nozzle to create eddies in the lower part of said chamber and thus oppose the flow of fuel to the nozzle in proportion as the depression at the nozzle increases, and a member located between the said chamber and the usual float chamber January, 1923.

GIACOMO MEMIN I. 

